The complete Radeon stack is now opened, from kernel driver (amdgpu) to OpenGL 4.5 (radeonsi), Vulkan (radv), DirectX9 (galliumnine) rendering and now OpenCL (rocm) computing.See that compatibility matrixIf you're running Linux, there is no point buying something else than an AMD Radeon and there is no point using something else than free software. No other vendor provides all these features, and AMD only provides that completeness with free software stack.